Determination Of Seven Fluorescent Whitening Agents In Whitening Masks By High Performance Liquid Chromatography

Fluorescent whitening agents are widely used in paper products, textiles and detergents and other products to enhance the whiteness and gloss of the products. Reports have pointed out that using detergents or paper products containing fluorescent whitening agents will cause the skin residue of them. These fluorescent whitening agents will increase the burden on the liver, cause the blood system damage, lead to cell mutation when combining with proteins in the human body which has the potential carcinogenicity. Therefore, corresponding regulations and standards have been carried out to supervise the use of fluorescent whitening agents in food packaging materials,dishwashing detergents and other products. However, there is neither regulation to forbid the use of fluorescent whitening agents in daily skincare cosmetics and masks, nor the corresponding measurement method. Some unscrupulous businessmen add fluorescent whitening agents in whitening masks to achieve whitening effect rapidly which poses a threat to human health.This paper was carried out to research the detection method for fluorescent whitening agents in whitening masks, which is of great significance for relevant institutions to strengthen supervision and management of cosmetic product quality and safeguard consumers’ health. In the selection of research objects, seven representative fluorescent whitening agents have been chosen considering the kinds of fluorescent whitening agents and its market usage; In the selection of detection methods, high performance liquid chromatography was selected. A method has been developed for the simultaneous determination of seven fluorescent whitening agents in whitening masks by high performance liquid chromatography-fluorescence detector(HPLC-FLD), throughthe optimization of sample pre-treatment conditions and detection conditions of HPLC-FLD.The research contents and results were as follows:In the study of pre-treatment of samples, ultrasonic extraction technology was the main method, and have designed single-factor experiment to optimize the conditions, and the optimum pre-treatment conditions were: the extraction solvent was 15 m L acetonitrile and ultrasonic extraction for 20 minutes at 30℃.In the study of the HPLC-FLD, this thesis examined the influence of mobile phase, gradient elution program, excitation wavelength and emission wavelength and column temperature on the separation and response value degree of seven components, and finally selected methanol-25mmol/L ammonium acetate as the mobile phases, the Agilent Eclipse XDB-C18 column for separation at 20 ℃, and detected by the fluorescence detector at an excitation wavelength of 365 nm and an emission wavelength of 430 nm, and realized simultaneous determination of seven fluorescent whitening agents in 38 minutes.The limits of detection for the method were 0.00071~0.18 mg/L and the limits of quantification were 0.12~12.24 μg/g. The recoveries at three spiked levels were between93.62%~115.87% with the relative standard deviations of 0.43%~5.40%. The method was simple,sensitive and accurate, and could be used for the determination of the seven fluorescent whitening agents in whitening masks. It also could provide scientific basis and technical support for relevant detection institutions to supervise commercial whitening masks.